Synonym or breeding number (also GM 3-37) for the grape variety Rotberger; see there.
The red grape variety is a new breed between Schiava Grossa (Trollinger) x Riesling. Synonyms are Geisenheim 3-37 and Redberger. Incidentally, the same parents also gave rise to the new varieties Kerner and Witberger. The cross was made in 1928 by Dr. Heinrich Birk (1898-1973) at the Research Institute...
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